Propeller



A. P. FILIPPI.

PRO`PELLER.

APPLICATION FILED AUG.24, I9I7.

Patented May 17, 1921. v

[Ime/fr pressure UNITED STATES PATENT OFFICE.

lAIv'IfoINE PAEoUE FILIPPI, 0E Paars, FRANCE, AssIGNoE rro HENRI JOSEPH LEON MARIE DE LA ,CHEVAEDIEEE :DE LA GRANDVILLE, 0E PARIS, FRANCE.

PEOPELLEE n Specification of Letters Patent. i

Patented May 17, 1921.

Application led August 24, 1917.v Serial No. 188,057.

To all whom t may concern I Y Beit known` that I, ANTOINE' PADoUE FILIPPI, citizen of the French Republic,` residing at Paris, France, have invented certain new and useful Improvements in Propellers, of which .the folloiwingV is a specification.k `Y A' Thepresent invention relates to a process and an apparatus for the manufacture of propellers having twisted blades with great accuracy, a maximum 0f strength and a minimum tendency to warping.

To this end the material from which a twisted bladek or Yblades is orare to be formed is clamped or pressed on a mold so ias'tol conform it to the desired curvatures on one face only,fpreferably ythe attacking or forward face of the blades, the other corresponding face being afterward worked to the desired `curvature by shaving off or otherwise removing the surplus material by the known methods.y

f' Heating means could bev used during the fmolding operation, but generally better re- 25.`

not used.

sults are obtainedif such heating means are According to the invention the material to be treated is a compound laminatedmaterial kconsisting of `a number of leaves of wood glued or cemented together. The said Aleaves of wood are of relatively small depth 'and' have a length and a width slightly greaterthan the length and the width of the propeller to be manufactured.' The total depth ofthe compound laminated material is preferably slightly greater than the depth of the central part of the propeller to. be manufactured. The compound laminated material is, after gluing or cementing of its leaves applied upon a mold or matrix the active surface `of which *forms the counter-part of the surface Aof the propeller which is to be obtained. The compound laminated material is then strongly Aand gradually pressed v.against the active surface ofthe moldl orfmatrix,` till it beds exactlyagainst the said active surface. The Y is maintained for a sufficient length of time to allowtheglue or cement to beentirely dry..' 'The pressure is thenL W xreleased, anda solid block is obtained hav ing one of its faces molded tol the form of removing the surplus material by the known methods for giving to its other'face the form corresponding to the other face ofthe propeller to be manufactured.

The annexed drawing shows by way olf example, one mode 'of constructing apparatus for the working of the process 1*; Igure 1 is a yperspective viewV of the m0 Y Fig. 2 shows thev whole of the arrangement entirely Imounted with a series of press-cramps in position for the molding of one face of the propeller,

Fig. 3 is a vertical transverse section made between two press-cramps showing the position of the various parts andthe leaves or laminations before pressing; this figure also shows in dot and dash lines,v the position which the laminations tend to take when the pressing'action commences.` 1

` Fig. 4 is a similar view showing the final position of the parts, when the molding is ynished and the -laminations have, as a result, exactly assumed the shape of the matrix.

pied by the presses; 'it is importantthat the i ,site should be exactly determined because as will'be described later, upper cramps of the presses are hollowed tothe transverse :profile of the matrix at thesectionunder consideration.

Upon the matrix'LvI apply (see Fig. 3) the series of leaves coated with glue or cement `and arranged like the leaves of a laminated metal spring. The matrix Iv and the laminationV 2 are held between presses of any suitable number; each fone of these presses (see` Figs. Sand 4)is formedfof an upper cramp 3 and a lower crarnp 3' con-` nected together by bolts' 55 serving to effect they necessarypressing action.- The lower cramp 3 is a simple piece of'y woodI ,'(or any other appropriate material) j intended to receive and support thematrix I; 'this piece is perforated at its ends with two .holes for the passagefof the bolts 5 and 5;

The `upper cramp '3 is notched or shaped liupon its vlower'face'to a profile 4 correspondthe corresponding face of the propellertob.1 be manufactured. The said block is afterward worked byshaving off or otherwise ing exactly for eachpress to the transverse profile of the matrix at the part whichis to receive the press considered. This oramp is alsoperforated at its end with holes corresponding to those of the lower cramp and intended for the passage of the bolts 5 and 5.

In the method of'execution illustrated, I utilize ten presses for the whole length of the matrix; it goes without saying that this number varies with the dimensions of the propellerwhich is to be obtained.

To effect a molding of the propeller, I commence by placing the matrix I upon the series of lower cramps 3', these cramps be ing distributed throughout the length of the matrix, at4 the points indicated by the mark` ings l. I afterward arrange upon the matrix the block of laminations 2, which have been previously coated with cement or glue, and, the bolts 5, 5 having been inserted throughv the holes ofthe lower` cramps, I put in place the series of upper cramps 3, passiing the upper extremities of the bolts through the holes in the said cramps. The upper cramps are, it is to be understood, 1arranged at the place of the markings 1 and in an order such that the profiles 4 of these cramps correspond with the transverseprofiles of the matrix at the points considered. The nuts are then screwed up on the bolts 5, 5 and tightened up at first lightl whereas afterward the pressure is gradually increased. The Vblock of glued laminations 2, which at the commencementof the operation was placed horizontally as shown in Fig. 3 (the central part ofthe saidblock bearing ,upon the lcentral part of the matrix) bends or sets during the screwing up action, :towardthe position indicated in dot and dash lines on Fig. 3. (It goes-without saying that, relatively to F ig. 3, the inclination of thebloclr 2 is made inthe opposite direction for the other half of the propeller). The pressing action isV progressively continued until the block is forced to bed exactly against the matrix (Fig. 4) the laminations moving slightly each upon the lower one according vto the incidence curvature of the lamination of the bloclr. The block is al* lowed to dry and when the drying vis perfect, I -dismount the series of the presses. One of the faces of thepropeller is thus molded; it can be (after touching up, if necessary) rubbed down 'and varnished` in the usual manner. Y y,

The other face is afterward made in the known manner by removing. the surplus material, e. g.,by planing, employing templets or gages to obtain the desired shape.

Ascomp'ared with an ordinary propeller blade made from laminated material, the present inventionenablesrme to forma propeller from laminations of the maximum width of the blade, like the leaves of a laminated metal spring` and with the" maximum vsurface for `the glue between adjacent'laminations, this result being obtainedby reason ofA the -mold affording the -desired `twist andv has become set.

consequently with maximum adherence between the laminations. In other words my invention insuresthe maximum surface of adhesion between adjacent laminations, whereas in ordinary propellers the small extent of the surface of adhesion is a weak Y point. In my construction the fiber of each vleaves which are of the full length ofthe propeller to be made, with an adhesive applied to their meeting faces, submitting such laminations, while the adhesive is unset, to compression between surfaces shaped to mold one side of the assembled laminations throughout the length thereof to the desired form, thusgiving the proper pitch and shape to the blades at the one` and same side of the propeller, and :maintaining such compression until the `adhesive has become set and capable of maintaining the Iaminations in molded form. i

2, The process for` the manufacture of propellers, which consists in compounding flat unshaped laminated-material 'all of the laminations being of the fulllength of the propeller to be produced,.the laminations extending across the transverse widthof each blade of the propeller, and' also continuously from one blade to another blade at the same side of the propeller, molding said material by pressure to :conform one face only of eachblade at the same side of the propeller to aprofiled mold or matrix which forms the counterpartofthe said face ofthe twisted propeller blades, and trim- Vming ofi' the surplus material from theother faces of the twisted blades to give :the same the finished form.

3. The herein described method of making propellers, which comprises superposing unshaped vlaminationsiof wood with an adhe'sive applied totheir meeting faces,` said Vlaminations extending continuously `between the blades and at lthe samesideof-thepropeller, .submitting the 1 superposed AAunshaped laminations, while the adhesive between their meeting faces is unset, tocompression between 'surfaces shaped tofmold the same into the desired formv to thus shapeone face of each blade at the same 4side of the-propeller, andto impartthe propertwist` tothe blade, and maintaining such fcompression until theadhesive between the laminations 4. A `propeller comprising superposed glued or cemented resilient laminations bent in shape to formtheblades, the'laminations so Y extending continuously from one blade to the other blade at the same side of the propeller, the blades being maintained in proper form and with the proper twist by the glue or cement which unites the laminations.

5. Apparatus for use in the making` of propellers, comprising a profiled matrix forming the counterpart of the blades and hub to be obtained, and a suitable number of presses to coperate with said matrix, each press having its lower face of a width to extend entirely7 across the blade of the proeller, said face having a profile correspondlng to the transverse profile of the portion of the matrix with which it cooperates.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ANTOINE PADOUII` FILIPPI. [L.l.]

Witnesses THOMAS HALE, EUGNE FULLIER. 

